Electrically operated timing mechanism



Aug. 30, 1932. c. FAYER 1,874,477

BLBCTRICALLY OPERATED TIIING IECHANISI Filed Kay 15. .1929 5 Sheets-Sheet 1 Charla? er mm; Km;

ATTORNEY Aug. 30, 1932. v cfii- 1,874,477

ELECTRICALLY OPERATED TIMING MECHANISM TJE'LJR a 2 Filed MawlS, 1929 5 Sheets-Sheet 2 INVENTOR Charla Edd/er ATTORNEY Aug. 30, 1932. c. FAYER 1,874,477

ELECTRICALLY OPERATED TIMING MECHANISM Filed May 15, 1929 5 sheets sheet 3 mama: S 14 IIHHH ATTORNEY Aug. 30, 1932. c. FAYER 1,874,477

' ELBCTRICALLY OPERATED TIMING MECHANISM Filed May 15, 1929 5 Sheets-Sheet 4 WEE ATTORNEY Aug. 30, 1932. g, FAYER ELECTRICAL-LY OPERATED TIMING MECHANISM Filed May 15. 1929 5 Sheets-Sheet 5 HHHH 1151151212.

Z8 cjzarzgjmlgmola 40 1'49 mm Mm l ATTORNEY Patented Aug. 30, 1932 UNITED STATES PATENT OFFICE CHARLES FAYER, 0F FLUSHING, NEW YORK, ASSIGNOR TO WAPPLER ELECTRIC COM- PANY, INC., A CORPORATION OF NEW YORK ELECTRICALLY OPERATED TIMING MECHANISM Application filed May 15, 1929. Serial No. 363,122.

My invention relates to electrically operated timing mechanisms for photography and various arts immediately associated therewith, in which a sensitized plateor film is to be exposed to the momentary action of light of any kind.

My invention admits of general use, but is specially adapted for X-ray work of a kind in which the exposure is of exceedingly short duration, and to very intense rays.

My improved timing mechanism is of the general typecontemplated by my Patent No. 1,842,596, of January 26, 1932; that is, a timing mechanism operated synchronously with an alternating current line and provided with a setting mechanism, controllable by the operator, i'or predetermining the'precise number of current impulses to be used for any given exposure, these impulses alone being used to energize the X-ray apparatus, and

the duration of these impulses being essentially the time period of the exposure.

By my invention I seek to accomplish a number of distinct objects, among which are the following:--

I. To provide a timing mechanism adapted for use with X-ray apparatus in which exceedingly heavy currents of very short duration are used, in order to bring out sharp delineation and prevent blurring, especially when the object photographed is in motion or is likely to move.

II. To provide the timing mechanism with control devices, operated synchronously from the line and under control of the operator, for energizing and d'e-energizing the X-ray apparatus at the exact instant required, in order to use a predetermined exact number of current impulses, all precisely alike, each impulse beginning and ending at the zero line of the alternating current sinus.

III. To provide means for avoiding undue arcing in either the primary or the secondary circuit, and to prevent the X-ray apparatus from being energized by fractional parts of a current impulse.

IV. To provide safety mechanism for preventing the timing mechanism, when set by the operator and caused to function as thus set, from repeating its function or any part thereof, unless again set for the purpose; although the synchronous motor and most of the movable parts driven thereby may run continuously.

V. To provide means for opening and closing'certain high tension switches in a predetermined sequence during the operation of the apparatus, in order to promote safety and asa further precaution against undesirable arcing.

VI. To use a timing mechanism in connection with a thermionic X-ray tube having a heat controlled cathode, and to provide means controllable by said timing mechanism for maintaining said cathode at a relatively high temperature during a period coinciding substantially with the period of exposure, thus tending to prolong the life of the cathode and X-ray tube.

VII To provide various parts, improvements and combinations, incorporated in or associated with the timing mechanism, for improving the efficiency thereof; all as set forth in the appended claims.

Heretofore in this art, X-ray tubes as used for photography have usually been energized by means of hi h tension transformers, the control of the X-ray tube bein attained in some instances by means 0 the primary circuit, and in others by means of the secondary circuit; but in either case much trouble has arisen, in the form of undue arcing whenever either circuit was opened.

Where the periods of exposure were not less than about of a second, and the secondary current required to energize the X-ray tube was not much over 100 milliamperes, the control of the X-ray tube. by means of the primary circuit has been carried out successfully. For shorter periods of exposure, with the heavier currents required, it has been impracticable to prevent undue. arcing, heating or burning at some point, no matter whether the X-ray tube was controlled from the primary circuit or from the secondary circuit. 7

Not only that, but whether the control of the X-ray tube was from the primary or the secondary circuit, and particularly if the period of exposure was short and the current was heavy, further trouble has usually deprimary winding, and thus when the primary winding is energized. Hence there must be arcingas the primary switch or 1ts equivalent is opened, and though an impulse Wlll be generated in the secondary Winding it will be of less than normal intensity, The secondaryimpulses thus produced are worse than useless, and the action upon the primary switch is more or less destructive.

By my invention am able to use exceedingly short periods of exposure and correspondingly heavy currents; andalso toopen and close both the primary circuit andthe secondary circuit, but without unduearcing and without excessive heating or burningof any part in either. circuit. l I also find itboth advantageous and'practicable, by means of my invention, to not onlyopen and close the primary circuit at moments when the voltage of the line'is at zero, but in sodoing to first take off the load from the secondary circuit, then close the primary circuit, then restore the load to the secondary circuit; then take off the load from the secondarycircuit, and finally to open the primary circuit. 7

. In thisway, the primary circuit is never opened or 'clo'sedat an instant when there is any load upon the secondary circuit, and the secondary circuit, even free from' load, is never opened or closed except when the primaryrcircuit is open. .Under the conditions just described, it is an easy matter to so adjust the various contact mechanisms of the secondary circuit as topreven-t arcing, undue heating or burning of any parts within any circuit. 1 My apparatus is made up in slightly different forms, the main difference between them being the manner in which the X-ray tube is protected, as against high tension discharges tending to pass through it in the wrong'direction. Y

' For this purpose, myinvention is adapted for use in different relations, as follows 7 First, as a combined rectifier and impulse timer; i V

Second, as incorporating a valve tube rec} 'tifier; and I l f Third, as incorporating a mechanical rectifier. I

Figure .1 is a plan view of my improved timing mechanism.

Figure2 is a vertical section on the line plate 16.

a larger scale.

Figure 6 is section on the line 66 of Figure 4, looking inthe direction indicated by the arrows. 1 V

Figure 7 is a'section on the line 77 of Figure 4, looking in the direction indicated by the arrows.

F igure 8 is a diagram of the wiring and Y shows a few mechanical parts not otherwise illu strated.

Figure 9 is a graph, indicating the develop ment of the secondary current in-a form of my device used as a combined rectifier and impulse timer, and shown in Figures 1 to 8 inclusive. Q J Figure 10 is a diagram of another form of my device, showin the same as incorporating valvetube r'ecti, ers. V v 8 Figure 11, is a graph, indicating the development .of the secondary. current in each of the forms of my device appearing in" Figures 10 and 12.

Figure 12is a diagram ofaform of my fdievlce as incorporating a mechanical rectier. 1 f

I will first describe the form of my invention appearing in Figures 1 to 8 inclusive,

and used as a combined rectifier and-impulse t mer..-

A tank appears at 8, and contains a volume of oil 9. The tank is provided with a cover .plate 10, which serves both as a closure member and as a 7 supporting table for various parts of themechanism. Mounted upon the cover plateis carries a worm 12, which engages and drives a worm wheel 13. f This worm wheel is mounted fixedly upon and carried by a drivbeing supported upon apa-irof frame posts 17, 18extending upwardly from the base The frequency of the alternating currents here assumed tobe sixty cycles per second.

The worm gear reduces the speed at the ratio of thirtyto one, and since the synchronous motor is a four pole machine and operates .at synchronous speed the vertical shaft 14 I a synchronous motor 11. The shaft of this motor Bil 'iss

used for energizing the synchronousmotor is found towork well in practice, as here used upon a conventional source of alternating current.

The vertical shaft 14 extends through a hole in the cover plate 10, and thus down into the tank. This vertical shaft carries a disc 19 of insulating material mounted fixedly upon its lower end thus located within the tank, and the disc 19 carries a clamp 20, shown more particularly in Figure 3,

Carried by the clamp 20 and extending directly downward therefrom are a pair of glass rods 21, 21, serving as switch posts.

Mounted upon the switch posts 21, 21 and spaced equidistant are spring holders 22, in this instance six in number.

Each spring holder 22 carries a pair of contact springs 23,24, spaced apart by braces 25 of insulating material. There are thus six pairs of these contact springs, the several pairs thereof being spaced equi-distant, as may be understood from Figure 4.

Mounted upon the cover plate 10 and extending downwardly therefrom are a pair of frame posts 26, 27, made of insulating material, and shown more particularly in Figure 2.

A metallic distributing bar 28 is mounted upon the lower ends of these frame posts, and thus disposed horizontally.

J ournaled upon the distributing bar 28 and extending upwardly therefrom are timing levers 29, 30, 31, 32, 33, 34, 35, 36, 37 and 38.

These timing levers are alike in construction. Each of them carries contact blades 39, in this instance seven in number. These contact blades are spaced equi-distant, and otherwise properly arranged to coact with contact springs 23, 24.

The timing levers are movable by hand, and adapted to be set or pushed forward one or more at a time. The contact blades of the particular timing lever or levers thus set are thereby brought into suitable position to be engaged, momentarily, by all of the contact springs 23, 24, during rotation of the disk 19.

Suppose, for instance, that the timing lever 29 aboveis set, the other timing levers remaining in their several normal positions, as indicated in Figure 4. This done, rotation of the disk 19 brings the contact springs 23, 24 into engagement with all of the contact blades 39 of the lever 29. The purpose of this arrangement of the contact springs 23, 24 and contact blades 39 is to subdivide, and thus virtually reduce, the voltage of certain high tension currents to be controlled, as hereinafter more particularly described, by aid of the contact springs and contact blades just described.

In each timing lever the lowermost blade 39 is permanently in metallic communication with a contact spring 40, which engages the distributing bar 28.

. The several timing levers extend through slots 42 in the cover plate, these slots being disposed radially with reference to the axis of rotation of the disk 19.

Extending through the cover plate 10 and upwardly therefrom are a pair of high tension insulating posts 43 and 44, through which extend the leads for energizing the X-ray tube. These leads are extended or continued below the ends of the insulator posts 43, 44, shown at 45 and 45a in Figure 2.

In the lower portion of Figure 2 is shown some high tension switch mechanism, cooperating as hereinafter described with the switch mechanism operated directly by movements of the timing levers.

A switch blade 46. of the type known as a finger blade, is made of aluminum, and is pivotally mounted upon the lower end of a large insulator 47, having the form of a switch post and extending downwardly from the cover plate 10. This post also carries a boxing 48, in the form of a split cylinder and serving as a housing for the pivotal mounting of the finger blade 46.

Mounted rigidly upon the distributing bar 28 and extending laterally therefrom is a contact plate 49, so arranged as to be en gaged by the finger bar 46, when the latter swings downwardly upon its mounting. By this arrangement, each time the finger bar 46 is broughtinto en agement with the contact plate 49, metallic communication is established from the lead 45 to the distributing bar 28.

The distributing bar 41 is provided with a number of contact springs 50, extending from it laterally, like the teeth of a comb. Each timing lever carries on its edge a small contact plate 51, held in position by a fastening 52 and so positioned as to have a continuous wiping or sliding engagement with the adjacent contact plate 50.

Each contact plate 51 is in metallic communication with the uppermost blade 39 of the adjacent timing lever. The arrangement is such that whenever a timing lever is set, as for instance the lever 29 in Figure 4, the two distributing bars 28 and 41 may be brought into metallic communication with each other through the medium of the contact springs 23, 24 as carried around, and the contact blades 39, as above described.

Hence the two distributing bars and 41 may be considered as a pair of high tension terminals, normally disconnected from each other, but adapted to be brought into conductive communication with each other by the travel of the contact springs 23, 24, after the setting of any one or more of the timing levers.

However, as may be seen from Figure 2, the distributing bar 28 has no connection with the lead 45 except through the finger blade 46, and only when the latter is in engagement with the contact plate 49. Hence In other words the main or high tension secondary circuit can not be closed except by means of a plurality of separate switches, acting interdependently. It must be closed by the setting of one or more of the timing levers, together with contact of the finger blade 46 with the contact plate 49.

. F or the purpose of actuating the finger blade 46 I connect it by a pivot 53 with a pitman 54. This pitman extends upwardly through a hole in the cover 10, and is connected with the'armature 55 of a relay 56, mounted upon the cover plate.

The relay is provided with a winding 57 and two separate contacts 58 and 59, as may be noted from Figure 1.

The armature 55 is so arranged that whenever the relay is actuated the descent of thearmaturethrusts the pitman 54 downward and causes the finger blade 46 to en gage the contact plate 49, thus closing the finger switch;

This same movement of the armature closes the two contacts 58 and 59, which control certain circuits as hereinafter described, and shown diagrammatically in Figure 8. I

Another relay 60 is mounted upon the cover 10. This relay is provided with two separate windings 61 and 62, adapted to be energized one at a time and independently of each other. This relay has a single contact 63, normally open.

The relay 60 is so arranged and its parts so adjusted that if the winding v61 alone is energized, the contact 63 does not close; but if-thereafter the winding 62 is also energized, the contact closes. If, next the winding 62 be de-energized, the contact remains closed until the winding 61 is also de-energized. The purpose of this arrangement is set forth below, in connection with the operation of he mechanism and in connection I with the description of the diagram shown in I so Figure 8.

Another-relay 64, preferably of masslve construction, is here mounted upon the wall secured to the shaft 14, and the disc is mounted firmly upon and carried by a sleeve 70a through which the shaft loosely extends. A spring 706 is wound around 7 thesleeve 70a, andis secured tothe disc '70 and to the framework. The disc 70 is controlled by the armature 68, so that whenever the winding 67 is energized, it lifts the sleeve 70a and clutch disc 70, so that the ,7

clutch disc 7 0 now turns with the shaft. The clutch disc 7 0, however makes only approximately three-fourths of a revolution after which it is prevented from further rotation by a stop pin not shown. Contact between the two clutch discs 69 and 70 is still maintained by relay 64a, but as the clutch disc 69 is being completely rotated by the shaft 14 and the disc 70 is prevented from further rotation there occurs a slippage'between the two discs.

The clutch disc 7 O'carries a pin 71, and mounted upon the frame post 18 is a contact 72, normally closed. This contact is opened by the pin 71 eachtime the disc 70 makes a 7 partial revolution in the direction of rotation of shaft 14 and is maintained open as long as he disc 7 0 is caused to contact the disc 69 by means of the relay 64a. The contact 72 is in series with relay 56, and when opthis circuit does not cause the contact 63 of thisrelay to open, because as elsewhere explained this contact is kept closed so long as the winding 61 remains energized.

The rotary contact 73 is so adjusted upon the shaft 14, and so proportioned and adjusted relatively to otherparts, as to close just before the contact springs 23, 24 engage,

the blades 39. In an apparatus of ordinary size, the contact should close when" the contact springs 23, 24, in moving toward the blades 39, are about an inch distanttherefrom, and thus at a moment which is a little prior to the closure of the fingerswitch within the tank.

The finger switch, whenever closed, remains closed until after the contact springs 23, 24, have made and broken engagement with the blades 39 of the timing lever or levers, and until the shaft 14 has made about three-quarters of a revolution.

The opening of the circuit through the finger switch is accomplished by the pin 71, carried by the clutch'disk 7 0, simply opening the contact 72, as above described; and this takes place when the shaft. 14 has turned about three-quarters of a revolution after the closure of the finger switch.

An X-ray tube is shown at 74 and is of the thermionic type. It is provided with a heatcontrolled cathode 75, which in this instance is a filament.

A small transformer 76 is used for supplying currents for heating the filament 75.

Electric power for the entire apparatus is supplied from a pair of alternating current leads 77 and 78.

From the lead 78 a wire 79, which is connected with a small hand switch 80, extends to the primary winding of the transformer 76, and from thence a wire 81 extends to a resistance 82, used in connection with the transformer 76 which supplies the currents for heating the filament.

A wire 83 extends from the resistance 82 to the lead 77. Two slides 84 and 85, operable separately and by hand, are used in connection with the resistance 82, for varying the amount of current supplied to the transformer 76.

From the slide 85 a wire 86 leads to the contacts 58 of the relay 56. From this contact 58, a wire 86a extends to the wire 81. From the contact 59 are wires 87, 101 and 89, the latter including a switch 90, extending to the lead 78.

When the switch 80 is closed the small transformer 7 6 is energized, and brought undercontrol. of the two slides 84, 85 and the contact 58, as hereinafter more fully described, so as to control the heating of the filament 75.

The anode end of the X-ray tube is connected with the high tension lead 45a. The cathode 75 of the X-ray tube is connected with a wire 91, which with another wire 92 extends to the secondary winding of the transformer 76, these two wires and the filament 75 comprising the secondary circuit of this transformer.

A wire 93 extends from the wire 91 to the secondary winding 94 of the main or high tension transformer 95, used for energizing the X-ray tube.

The primary winding of the main transformer is shown at 96, and from it a wire 97 extends to the lead 7 7 A wire 98 extends from the primary winding 96 to the contact 66 of the relay 64, and 55 from the armature of this relay a wire 99 extends to the switch 100. This switch is connected with the 1ead'7 8, and is operated by hand.

Connected with the wire 89 is a wire 101,

60 and from this wire a short wire 102 leads to the winding 61 of the relay60.

A wire 103 is connected with both wires 101 and 102, and leads therefrom to the contact 7 A wire 1041s o nec ed with the wire 103 and the'contact 72, and extends to the rotary contact-73. 7

From the rotary contact 73 a wire 105 leads to the upper winding 62 of the relay 60. From this winding a wire 106 leads to the lower winding 61 of the same relay.

From the armature winding 65 of the relay 64, a wire 107 extends to the contact 59 of the relay 56, and from the winding 57 of this relay a wire 108 leads to the contact 72.

Connected with the wires 87 and 101, at the junction thereof, is a wire 109 which leads to the winding 67 of the relay 64a, and from this winding a wire 110 leads to the winding 57 of the relay 56, and a wire 111 leads from the winding 67 to the armature 63 of the relay 60.

A wire 112 is connected with the lead 77, and is joined to three wires 113, 114 and 115. The wire 113 is joined to the winding 61 and wire 106 extendin to the winding 62. The wire 114 leads to the contact 63 of the relay 60, and the wire 115 leads to the armature winding 65 of the relay 64.

For the purpose of operating the synchronous motor 11, as energized from the leads 77 and 78, I use two wires 116 and 117, and a hand switch 118.

In arranging the apparatus for timing an exposure, the first step is to determine the length of exposure required, as in this particular instance measured in terms of onehundred and twentieths of a second. This done, we know how many of the hand levers 29, 30, 31, 32, etc., are to be set; and the required number is thereupon set accordingly.

Next the filament controlling circuit is adjusted, and then the hand switches are all closed, the last one preferably being the switch 90.

By closing the hand switch 90 a circuit is completed through the lower winding 61 of the relay 60, and this circuit may be traced as follows: lead 78, hand switch 90, wires 89, 101 and 102, lower winding 61 of relay 60, wires 113 and 112 to the lead 77, thence to source of electricity, and back to lead 78.

The completion of the circuit as thus traced energizes the lower winding 61 of the relay 60; but this merely improves the general holding qualities of the relay 60, and has no immediate effect otherwise. 1

Rotation of the vertical shaft 14 now closes the rotary contact 73 at the upper end of this shaft, which completes a circuit through the upper winding 62 of the relay 60, and this circuit may be traced as follows: lead 7 8, hand switch 90, wires 89, 101, 104, contact 73, Wire 105, upper winding 62 of relay 60, wires 106, 113 and 112 and lead 77 to source of electricity, thence back to lead 78.

The circuit thus traced, by energizing the upper winding 62 thereupon confers upon thisrelay its full power, the lower winding 61 having been already energized beforehand, as above described. Therefore the contact 63 closes, and this completes a-circuit through the winding 67 of the-re1ayf64a.

.-This circuit may be traced as follows :flead -78,hand. switch'90, wires 89, 101, 109, winding 67,wire111, contact 63 ofrelay 60, wires 1'14..ancl112,;.lea'd 77 to source of electricity, aand thence backto lead7 8.

Thewinding 67 of the relay 64a being thus energized, ithe armature .68 of this relay is is held in engagement therewith as 'long as The closure of the contact 63 of the relay also completes .a circuit through thegpm contact 72 which is normally closed and through the-winding 57 of the relay. 56. This circuit may be traced as follows Lead :78,

hand-switch 90, wires 89,10 1, 103, pincontact72, wire,108,winding 57 of relay 56, wires 110 and 111, contact 63 of relay 60, wireslla -and 112,, lead 77 to source of electricity, "and :thenccbackto lead78.

The circuitijust traced ismaintained only during about three-quarters of thetime re- 1 quired for asin-gle revolution of the shaft 14,

and is. opened by thepin7l'when it-reaches. .and opens the pin: contact 7 2, whi-ch is. normally closed. .Thefclutch disc 70 will remain .in'this position andemaintain. the pin contact 72- open as, long. as relay 64a remains ener- ,,gized andv this. latter relay remains energized as longflas the contactinember 63 is closed.

7 Upon the opening of contact member 63 and the resultingde-energization of relay 64a, the V. clutchudisc70 isrotated by the spring 7 05in a direction opposite to that of the rotation'of ishaftli thus causing disengagement of'the clutch discs 69 and70v and the restoration-of .the.

.tion.

pincontact 72to its normal closed posi- WVhen the winding 57 of-the-relay56 is energized by the closure of the circuit last above Ltraced, this relayis actuated and theconse- .quentmovement of this armature 55 thrusts the pitman 54: downwardly, thus bringing the finger? blade46' into engagement with the contact plate 49 and thereby closing. the high tension finger switch, as above described.

This movement of the armature 55 "also 7 causes the closure of the two contacts 58 and -59,,controllable'. by the relay 56. The closure of the contact 58 completes a circuit for controlling the currents used for heating the filament, and which maybe-tracedas follows Lead 78, hand switch 80, wire 79, primary winding of small transformer '76, wire 86a, contact'58, wire 86, slide 85, a small por- "tion of resistance 82,,sli'de'84, wire'83,lead 7 7 to source of electricity, and thence back to lead "7 8.

-The circuit thus-traced has the e'ftectof .X-ray tube.

' marten? boosting the amount of current passing through the small-transformer 76.1 -In this c'onnectionitshculdbe noted that-,before' the contact'58 is closed 'bythe relay 56,-a circuit a can he traced'through thesmall transformer;

76, as follows:

.Hand SW1lCl1'80,fWlIQ 79, primary winding of small transformer 76, wire 81, a relatively large portion of the resistance 82, slide 84 'wire 83, lead 77 to source of electricity, andithence back to the lead 78.

Thisi last mentioned circuit is one which normallyheats the filament. Being one of relatively highv resistance, itallows a relatively resistance 82, suddenly permits a larger amount of currenttc pass through the pr"- this account, the filament 75 is heated to a comparatively high'temperature by virtue of the action of the contact 5-8.

In practice, the circuits just traced" through the a primary winding of the transformer 76 30 are soapnortioned that normally the filament is-maintaine'd at a low red heat, and is then boostedto bright incandescence.

The purpose of this arrangement is to consmall quantity of current topass through the 'gg transformer 7 6; whereas the closure of the contact 58, by short circuiting a portion of the .mary windingof the transformer 76. Onbg;

serve the life of the filament, and by so doing to lengthen .the life of the X-ray tube. This is done, essentially, by maintaining the temperature of 'thei'filament sufficiently lowto give a'widemargin of safety for the Xray tube, wep i g he precise period re-- 1 quired for the X-ray exposure, and during that'short period to maintain the temperature ofctheifilament at the maximum allowed "for it duringthe actual operatlon'of the relay The closure ofthe contact 59 of the 56 closes a circuitthrough the armature winding 65 of the relay 64, and this circuit may be traced as follows: lead 78', hand its switch -90,"wires 89, 101, 87 contact 59, wire'f 107 ,narmature winding 65 of relay 64:, w res and'112 to lead 77, then-ceto source of elec- 'tricity and back to lead 78.

The relay 64,-being thus energized, closes "its contact 66, and thereby completes the cir-l f cuit' through the primary winding 96 of the main transformer, as follows: lead 78, hand switch 100, wire 99, contact 66 of switch 64:, wire 98, primary winding 96, wi re 97, lead 77 to source of electricity, and thence back to? lead 78.

The energizing of the relay56, and consequent downthrust of thepitman 5 1 operated thereby as elesewhere described, lowers the finger blade 46, and as the primary circuit is now closed as'justexplained, the secondary winding 94 is in action.

A high tension circuit, now completely un der control of the high tension rotary switch located within the-tankand carrying the con-' tact springs 23 and 24, may now be traced as follows:

Secondary winding 94 of main transformer, wires 93 and 91, X-ray tube 74 with its heated filament 75, high tension lead i5a, distributing bar 41, sliding contact mechanism 51, 50, thence in series through the blades '39 and contact springs 23, 24, distributing bar 28, contact plate 49, finger blade 46 (now depressed) high tension lead 45, back to secondary winding 94.

The circuit just traced is the one which energizes the X-ray tube, and it remains active for one or more periods of time, each very short but very definite.

At the end of the period of exposure, the clutch pin 71 in making a partialrevolution opens the contact 72; and this, by de-energizing the relay 56, brings about, more or less indirectly, three distinct objects, namely, the opening of the high tension finger switch, the restoration to normal condition of the circuits for controlling the temperature of the filament, and the opening of the circuit through the primary winding of the main transformer.

Next, the rotary contact 7 3 at the top of the vertical shaft 14 opens the circuit through the winding 62 of the relay 60, but this has no effect upon the winding 61 thereof, so the contact 63 of this relay remains closed.

Then the hand switch 90 is opened, and this breaks the circuit through the Winding 61 of the relay and restores this relay to its normal condition of inactivity. Finally the switch 80 and 100 are opened, thus leaving the apparatus as it stood at the beginning.

To make another time exposure of the same kind, the hand switch 90 and the other hand switches are simple closed. This causes the cycle of operations to be repeated.

For an exposure of a longer period of time, the proper number of the timing levers 29, 30, 31, 32, etc., are set, and the respective hand switches are closed, as before.

It will be noted that if after an exposure none of the hand switches are opened, and the apparatus is not otherwise disturbed, the synchronous motor will keep on running, but

' the exposure will not be repeated. This is due to the fact that the circuit to the relay 56 is maintained open at the pin contact 7 2 by the pin 71 carried by the clutch disc 70. In this manner even though the circuit to the relay 56 is partially completed by hand switch 90 and the contact member 63 it is not again energizable until the contact member 63 is caused to open by ole-energizing winding 61 through the opening of the hand switch 90. Upon the opening of the contact member 63 the relay 64a is de-energized which again causes closure of the pin contact 72 and prepares the apparatus for another exposure. In order to repeat the exposure, the

'* entire cycle of operations must be gone through again, beginning, of course, with the manipulation of the hand switches and the setting of one or more of the timing levers.

It will also be noted that the action of the mechanism as a whole is such that during any period of exposure for instance an exposure of one-one hundred and twentieth of a second, as determined by the setting of some one of the timing levers, say the one numbered 29, the exposure begins and ends at moments when the potential of the line is at zero. By virtue of this fact, sparking is prevented.

In the particular mechanism here illustrated and described and in which no rectifying device is used it is desirable, in order to protect the X-ray tube from high tension discharges tending to pass through it in the wrong direction, to suppress or render inactive one-half of the pulsations otherwise de veloped in the secondary circuit of the main transformer.

This object is readily accomplished by so arranging the contact springs 23, 24 and parts carrying the same as to prevent these contact springs coming into engagement with the switch blades 39, except at proper time intervals for the high tension currents to pass, in the right direction, through the X- ray tube.

This arrangement means, essentially, that the timing levers should be so positioned that the spaces between them have each the same proximate width as the thickness of one of" the levers, and so that relatively to the rotation of the contact springs 23, 24, the levers are alternated with the intervening spaces, and that these contact springs are necessarily idle during one-half of the time while the contact springs 28, 24- are passing such of the timing levers as have been set. This much granted, it is an easy matter to so propor tion, arrange and adjust the various parts that whenever the contact springs 23, 24 are in engagement with the blades 39, useful secondary pulsations and nothin else must pass in the proper direction through the X-ray tube; and conversely, whenever the contact springs 23 and 24 are between the blades 39, all useless pulsations, tending to pass in the wrong direction through the X-ray tube, are completely suppressed.

Figure 9 is a graphic illustration of the, high tension sine waves developed in the form of my apparatus above oescribed in con nection with Figures 1 to 8 inclusive.

Each sine 119 indicates one-half of a complete cycle and represents a high tension negative current passing through the X-ray tube, from right to left according to Figure 8. Each space 120 indicates the suppression of the other half of each complete cycle, such as if developed would tend to pass through the X' ray tube from left to right according the vacuum tube 122.

A Wire 128 is connected with the secondary winding 94, and with two wires 129 and 130,

leading respectively, to the cathode of valve tube 123 and the anode of valve tube 124.

A wire 131 is connected with the wire 92 and also with two wires 132, 133, these two wires leading respectively to the anodes of valve tubes 122 and 123.

A wire 134 is connected with the respective cathodes of the two vacuum tubes 121 and 124. This wire'134 is also connected with a wire 135, leading to the high tension rotary switch above described at length, and which as a I whole is'for convenience here designated by the single numeral 136.

The purpose of the valve tubes is to rectify the high tension currents which are to pass -hrough the X-ray tube, so that all currents passing through the X-ray tube will be negative currents, passing from right to left according to Figure 10, none of the high tension currents being suppressed.

By virtue of the action of the vacuum tubes, there are two secondary circuits which 'may be traced upon Figure 10. One of these circuits may be traced as follows Secondary winding 94, w1res'125 and127, valve tube'122, w1res132 and 131, X-ray tube '74, lead 450:, finger switch members 46, 28,

high tension rotary switch 136, wires 135 and 134, valve tube 124, wires 130 and 128 back to secondary winding 34.

When the potential of the secondary winding 94 is reversed, another clrcuit may be traced, as follows Secondary winding 94, wires 128 and 129, valve tube 123, wires 133 and 131, X-ray tube 7 4, lead 45a, high tension finger switch members 46, 28, high tension rotary switch 136,

wire 135, valve tube 121, wires 126 and 125,

back to high tension secondary winding 94.

It will be noted that in each of the circuits just traced the high tension currents pass in the same direction through the X-ray tube, and thus that rectification takes place.

The graph shown in Figure 11 indicates the form of the secondary currents; in the circuits just traced. There are a number of lines 137, all precisely alike, and each representing a half cycle.

' In the form of my device appearing in Figure 12 a wire138 leads from the secondary winding 94 to a mechanical rectifier 139, and

from the latter a wire'1'40 leads back' to the secondarywinding 94. g V

A -wire 149 leads from the mechanical rectifier to the high tension switch 136, and another Wire 142 leads from the mechanical rectifier to the wire 92.

With the form of my invention shown in Figure 12 two high. tension circuits canbe "traced in the same direction through the X- ray tube 74, these two circuits dilfering with varying condition of themechanical rectifier 139, which is run synchronously with the transformer 95.

One of these circuits may be traced as fol- V be traced as fol The half cycles of rectified currents due to the action of this form of the apparatus are identical in form with thoseproduced by the mechanism shown in Figure 10,"and are thus properly represented bythe graphic lines 137, in Figure 11.

It is wellwithin the province of 'X-ray engineering, in this state'of the art, to make other adequate provision for protecting the X-ray tubes against the development of high tension pulsations having a tendency to pass in the wrong direction through the X-ray tube. 1 do not deem it necessary to pursue this branch of the subject.

The operation of my device may be readily understood from the foregoing description.

The period of exposure having been decided upon, the person or object to be photographed is placedin position, the timing lever or levers for determining the desired. length ofthe exposure are set, and the various hand switches are closed, as above described.

I find in actual practice'that by means of my invention it is practicable to make large photos, very exact and clean-cut as to definition, where the period of exposure is only one-one hundred and twentieth part of a second.

I also find'that with the very short exposure just mentioned it is an easy matter to make a life-size X-ray photograph of the heart of a living person, every detail being delineated with the greatest clearness, the lines being distinct and sharp, and there being no noticeable blurring due to any muscular contractlon or other. movement ofthe heart.

I do not limit myself to the precise mech-' anism shown and described, as variations may be made therein, without departing from my invention, the scope of which is commen- 10 surate with my claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is as follows:

1. An electrically operated timing mechanism, comprising an alternating current line, a high tension transformer provided with a primary winding and a secondary winding, said primary winding being adapted to be connected with said line, an X-ray tube, ahigh tension circuit including said X-ray tube and the secondary winding of said transformer, said circuit being normally open, and a timing device adapted to be connected with said high tension circuit to cause a predetermined exact number of current impulses to pass from said secondary winding to said X-ray tube.

2. An electrically operated timing mech-' anism, comprising an alternating current line,

a a high tension transformer provided with a primary winding and a secondary winding, said primary winding being adapted to be connected with said line, an X-ray tube, a

high tension circuit including said X-ray tube h and the secondary winding of said trans- 35 former, said circuit being normally open, and a timing device adapted to be connected with said high tension circuit for closing the same through said X-ray tube, said timing device having means whereby it may be set by the operator, to cause a predetermined exact number of current impulses as required to pass from said secondary winding to said X-ray tube. Y

3. An electrically operated timing mecha nism, comprising an alternating current line, a synchronous motor adapted to be connected with said line and energized thereby, a high tension transformer provided with a primary winding and a secondary winding, said primary winding being adapted to be connected with said line, an X-ray tube having an anode and a'heat controlled cathode, a high tension circuit including said X-ray tube and the secondary winding of said transformer, said circuit being normally open, a timing device connected with said high tension circuit for closing the same through said X-ray tube, said timing device having means whereby it may be set by the operator, to cause a predetermined exact number of current impulses as required to pass from said secondary winding to said X-ray tube, a circuit connected with said heat controlled cathode for energizing the same, and mechanism connected with said last mentioned circuit and controllable by said synchronous motor for momentarily in creasing the supply of heatin currents.-

4. An electrically o erate timing mecha' nism, comprising analternating current line, a synchronous motor adaptedconnected with said line and energized thereby,a highten'sion transformer provided with a primary winding and a secondary winding, said primary winding being adapted to be connected with said line, an X-ray tube having an anode and a heat controlled cathode a high tension circuit including said X-ray tube and a secondary winding of said transformer, said circuit being normally open, a timing device connected with said high tension circuit for closing the same through said X-ray tube, said timing device having means whereby it may be set by the operator, to. cause a predetermined exact number of current impulses as required to pass from said secondary windin to said X-ray tube, a circuit connected wit said heat controlledcathode for energizing the same,sai d circuit including a resistance controllable by the operator for permitting a small amount of current to pass through said circuit in order to heat said filament to :1 limited extent, and mechanism connected with said circuit and controllable by said synchronous motor for cutting out a portion of said resistance.

5. An electrically operated mechanism for X-ray work, comprising an alternating current line, a synchronous motor adapted to be connected with said line, a high tension transformer, an X-ray tube connected with said high tension transformer and provided with a heat controlled cathode, a small transformer connected wtih said cathode for sup lying heating currents thereto, mechanism adapted to be connected with said X-ray tube and driven by said synchronous motor for closin a' high tension secondary circuit from sai high tension transformer through said X-ray tube, a circuit including said heat controlled cathode in order to supply heating currents thereto, and mechanism connected with said last mentioned circuit and controllable by said synchronous motor for momentarily increasing the supply of said heating currents.

6. An electrically operated timing mechanism, comprising an alternating current line, a synchronous motor adapted to be connected with said line and energized thereby, a high tension transformer having a primary winding and a secondary windin a circuit connected with said line and inclu ing said primary winding, another circuit connected with said secondary winding and including said X-ray tube, each of said circuits being normally 0 en, and mechanism connected with said circuits and controllable by said synchronous motor for first closin said primary circuit and then closing sai secondary circuit.

7. An electrically operated timing mechanism, comprising an alternating current line,

' a synchronous motor adapted to be connected 1 5 11, e rr i s nected withsaid line and including said pri- 2s:

with said line and energized thereby, a high tension transformer having a primary windingfand a secondary winding, a circuit connectedzwith said line and including said primary;winding,another circuit connected with said secondary winding and. including said X-ray tube, each ofsaid circuits being normally-ope nmechanism for closing and opening ,said first mentioned circuit, mechanism for closing and opening said second n1entiojned' circuit, and mechanism common to bo h circuits and: controllable by said synchronous motor for; determining a definite order ofsuccession in which said circuits are opened and closed. 7 V 1 in electrically operated timing mechaan alternating current line, a synchronous motor adapted to be connected with said line and energized thereby, a high tension transformer having aprimary wind-v ing and a secondary winding, a circuit conmary winding, another circuit connected with said secondary winding and including said X ray'tube, each-of said circuits being nor mally open, mechanism connected with each of said, 'circuits and controllable by said synchronous motor for closing and-opening each of said circuits, and mechanism controllable said synchronous motor for pre-' venting successive Inenti-onedcircuit. a

9, An apparatus comprising an alternating current line, a high tension transformer adapted to be connected with said line and adaptedto be energfzedthereby, an X-ray tube, a hightension circuit connected with closures of said second i said transformer and including said X-ray tubein order to enable said transformer to energize said X-ray tube, said circuit being normally open, and two high tension switches included in said circuit'and controllable by said synchronous motor, one of said switches being.supervisory in relation to the other, and

' other one of said hi h tension switches bein connected-with, said synchronous motor and thereby driven inter-dependently for the purpose of closing. said circuit. r

'11. An apparatus comprising an alternatingcurrentline, a synchronous motor and a high tension transformer adapted to be con? nected withsaid line and adapted to be'energized thereby, an X-ray tube, a rotary switch arm driven by said synchronous motor and carrying a plurality of contact members, a

plurality of timing levers each provided with contact members mating said contact memmembers of said switch arm and the contactmembers of such ofsaid timinglevers as have been set by the operatoni 12. An; apparatus comprising an alter nating current line, a synchronous motor and a high tension transformer adapted to be connected with said line and adapted to be energized thereby,anAX-raytube, a rotary switch arm driven by said synchronous motor and carrying a plurality of contact members, a plurality of timing levers each provided with contact members mating said contact members of said switch arm,-said timing levers-each being disposed adjacent said switch arm and nor-- mally stationary, but movable in order to be set by the operator for the purpose of bringing its contact members partially into the path oftravel of said contact members of said switch arm, a high tensioncircuit connected with said transformer and energized thereby, said circuit includingsaid X ray tube and also including said contact members of said switcharm andthe contact members of such of said timing levers as have been set bythe operator and means controllable by said synchronous motor for normally preventing the repetitious closing of the circuit through said X-ray tube. r

13. An apparatus comprising an alternating current line, asynchronous motor and a high tension transformer adapted to be connected 'with'said line and adapted to be energized thereby, an X-ray tube, a rotaryswitcharm driven-by said synchronous motor and carrying a plurality of contact members, a plurality of timing levers each provided with contact members mating said contact members of said switch arm, said'timing levers each being disposed adjacent said switch arm and normally stationary, but movable in order to be set by the operator for the purpose of bringing its contact members partially into the path of travel of said contact members of said switcharm, a hightension circuit connected with said transformer and energized thereby, said circuitincluding said X-raytube and also including said contact members of said switch arm and the contact members of such of said timing levers as have been set by the operator, said circuit also including a finger switch controllable by said synchronous motor for normally preventing the repetitious closing of the circuit.

14. n apparatus comprising an alternating current line, a synchronous motor and a high tension transformer adapted to be connected with said line and adapted to be energized thereby, an X-ray tube, a high tension circuit connected with said transformer and including said X-ray tube, a revoluble switch member connected with said synchronous motor and having a plurality of contact members, and a plurality of timing levers arranged to be included in said high tension circuit and each provided with contact members mating said contact members of said switch members and disposed partially within the path of travel thereof in order to prevent the contact members of said revoluble switch member to complete said high tension circuit through said timing levers to said X-ray tube, the adjustment of said revoluble switch members to said synchronous motor being such that the engagement and disengagement of said contact members takes place when the potential of the line is at zero.

15. An apparatus comprising an alternating current line, a synchronous motor and a high tension transformer adapted to be connected with said line and adapted to be energized thereby, an X-ray tube, a high tension circuit connected with said transformer and including said X-ray tube, a revoluble switch member connected with said synchronous motor and having a plurality of contact members, a plurality of timing levers arranged to be included in said high tension circuit and provided with contact members mating said contact members of said revoluble switch member and disposed partially within the path of travel thereof in order to permit the contact members of said revoluble switch member to com lete said high tension circuit through said timing levers to said X-ray tube, and means for directing the high tension discharges of said high tension circuit all in the same direction through said X-ray tube.

16. An apparatus comprising an alternat ing current line, a synchronous motor and a high tension transformer adapted to be connected with said line and adapted to be energized thereby, an X-ray tube, a high tension circuit connected with said transformer and including said X-ray tube, a revoluble switch member connected with said synchronous motor and having a plurality of contact members, a plurality of timing levers arranged to be included in said high tension circuit and provided with contact members mating said contact members of said revolugement of said contact members takes place 7 when the potential of the line is at Zero.

Signed at Long Island City, in the county of Queens and State of New York, this 11th day of May, 1929.

CHARLES FAYER. 

